An air bag circuit of an automobile contains male and female connector housings which mutually fit together, either one of the male or female of these connector housings containing ferrite for the purpose of noise reduction. In the usual case, the fitting portions of the male and female connectors have the same specification. However, there is a possibility that the specifications are not the same, depending on whether the ferrite is housed in the male or female connector housing. In these circumstances, when the male connector and the female connector, having differing production patterns, are fitted together, two types of connector housings are produced, those which are able to contain ferrite and those which are not, in order to correspond to the presence or absence of ferrite in the corresponding connector housing. By this means one can avoid the waste of having ferrite within both the male and female connectors, or the problem of having ferrite in neither the male or female connector.
In general, the shape of connector housings is complicated due to the fact that they must house terminal fittings, and consequently moulding cost are relatively high. Moreover, in the case of conventional connectors, in the case where the connector is adapted to the corresponding connector which does or does not contain ferrite, two types of connector housings must be produced, one for containing ferrite and the other not. Consequently, there is the problem that production costs rise, and confusion may be possible due to the number of different mouldings. The present invention has been developed after taking the above problem into consideration, and aims to present a connector housing in which the connectors have common features, and in which costs are reduced.